Combination stop mechanism



3 Sheets-Sheet l R. F. MOIQK COMBINATION STOP MECHNISM Nom 27, 195]Filed Nov. 26, 19

Nov. 27, 1951 R. P. MCRK COMBINATION STOP MECHANISM 3 Sheets-Sheet 3Filed Nov. 26, 1948 IN V EN T OR.

ATTORN EYS..

Patented Nov. 27, i951 2,57 6,764 COMBINATION STOP MECHANISM Raymond P.Mork, Cincinnati, Ohio, assignor to The Baldwin Company, Cincinnati,Ohio, a corporation of Ohio Application November 26, 1948, Serial No.62,180

21 Claims.

My invention relates generally to means for opening or closing electriccircuits individually or in selected combinations, manually orautomatically. I shall describe my invention in connection with anexemplary embodiment which is a combination stop action employable inelectrically controlled pipe organs, or in organs of the type whereinelectrical pulsations are generated, cornbined, modied as to harmoniccontent, and converted into audible musical tones.

A primary object of my invention is the provision of a simple,inexpensive, but completely flexible organization whereby, by means of asingle actuator, various preset combinations of electrical circuits maybe energized.

It is an object of my invention to provide a simple and dependablemechanism by which an operator may, after depressing a selecting buttonor the like, set up desired electrical circuits for energization, and,releasing said button, obtain at a later time energization of the samecombination of electrical circuits by pressing the same selectingbutton.

It is an object of my invention to provide a mechanism of this classwhich is economical, dependable, durable and easy to assemble andadjust.

It is an object of my invention to provide a mechanism of the characterdescribed well adapted for inclusion in a removable voice box in anelectrical musical instrument, as hereinafter described.

Another object of the invention is to provide a mechanism of the classset forth by means of which an operator may quickly alter thecombination of electrical circuits previously chosen, upon the actuationof a different selecting button.

Still another object of the invention is to provide a combination stopaction for a musical instrument, by means of which electric stopswitches may be actuated separately or in selected combination, manuallyor automatically.

Yet another object of the invention is the provision of a mechanismwhereby a series of electrical circuits may be energized inpredetermined sequence by an actuator for that purpose, as for example apedal which gradually brings into play all stops of the full organ whendepressed, without interfering either with the manual selection ofstops, or with the operation of combination mechanism such as thatreferred to above.

These and other objects of the invention, which will be set forthhereinafter or will be apparent to one skilled in the art from thefollowing description, I accomplish by that construction and arrangementof parts and in that mode of operation of which I shall now describe theaforesaid exemplary embodiment. Reference is made to the accompanyingdrawings wherein:

Figure 1 is a partial plan View of my combination stop mechanism.

Figure 2 is a partial vertical sectional view taken along the sectionline 2-2 of Figure 1.

Figure 3 is a transverse vertical section taken along the line 3-3 ofFigure 2.

Figure 4 is a partial vertical transverse section taken along the line 44 in Figure 1.

Figure 5 is a partial elevation with portions in section taken along theline 5-5 of Figure 3.

Figure 6 is a partial sectional view taken along the line 6 6 of Figure4.

Figure 'l is an enlarged elevational view of a cam which I may employ.

Figure 8 is a simplified and semi-diagrammatic perspective view, withparts in section, of the combination mechanism showing also circuitarrangements therefor.

Figures 9, 10 and 11 are respectively elevational views with parts insection showing the mode of operation of a portion of the combinationmechanism.

Figure 12 is an elevational View with parts in section showing theorganization of the combination modifying devices.

In a musical instrument of the organ type, the various voices andcouplers are usually selected by means of stop tabs in the form of shortlevers projecting through an aperture in the top front board of theinstrument above the playing keys, and having upper and lower positionsin which appropriate electrical circuits are energized andcle-energized. Various voices and/or couplers or combinations thereofare desired during the performance of most musical compositions, and theplaying must be partially or wholly interrupted to permit the organistto depress or raise pluralities of the stop tabs. This operation isinconvenient and time-consuming. As a consequence, there has hithertobeen recognized the need for the provision of combination stopmechanisms whereby a plurality of predetermined voice combinations couldbe set up on a program apparatus and then obtained instantly andselectively through the actuation of single buttons, stop tabs or thelike. Mechanisms hitherto proposed for his purpose have, however, beencumbersome, expensive, and in most instances difficult to set up andadjust.

In a copending patent of John F. Jordan, No. 2,555,040, dated May 29,1951, there is described an assembly of parts in an electrical musicalinstrument in which complex electrical pulsations are generated for allof the notes within the range of the instrument, these pulsations beingthereafter combined in accordance with the requirements of a musicalcomposition by means of playing keys, the so-combinedoscillations beingnally -modiiied selectively by voicing cir.- cuits, amplied andreproduced. In the construction of this organ, the stop tab mechanisms,lthe stop tab switches, the various Voicing `circuits, electronicout-phasing means, and a preamplier are all assembled as a unit in aVvoice box structure. This unit is removable and replaceable in the organas such, being located behind the upper iront board 4of the instrument,with the stop tabs projecting through openings therein. The voice boxhas plug-in connections to a connector board wired to the key switches,and also plug-in connections to various ,other in- Vstrumentalities suchas a distributor box for connection to the volume control and to theamplier and reproducer mechanisms. ',Ihe voice box may also containswitch mechanisms for tremolo, echo organ and the like additionallyprojecting through the upper front board of the instrument. Thecombination `stopand other devices taught lin .the present ,applicationare well adapted for installation in a unitary voice box structuregenerally of the type described in said Patent No. 2,555,040, with suchchanges in dimensions of vthe voice box as may be required toaccommodate theaddedapparatus.

Stop tab and switch mechanism As most clearly shown in Figure 4 eachstop tab I is provided with a hub II Vresting on an upwardly extendingiin of a bar I2, `xed in the organ, or forming a part of the voice boxhereinabove referred to.V Aflixed to each stop tab there is an elementproviding an upwardly extending arm I3 notched at its upper end, and avvrearwardly extending arm I4. A compression spring I5 engages betweenthe notch of the arm I3 and an overhead abutment I6 on the` organ frontboard or voice box, forming a dead center mechanism, tendingto hold thestop tab down upon the bar iin, and holding it either in the olfposition shown in solid lines in Figure 4 or in -the on position shownin d otted'linesy in the same gure.

A stop switch is generally indicated at IT, having an actuating plungerI8.. The stop switches are preferably, though not necessarily of theform described in Patent 2,215,124, dated September 17, 1940, in thenames of Kock and Jordan. I have shown an operating lever I9 attached tothe switch by a resilient member 20 and having an overhead abutment 2|`to be engaged by a nger 22l attached tcthe rearwardly 1,

plied in the organ so that there will be one such assembly for eachvoice for each of the manuals of the organ. Preferably all of the stoptabs will be mounted in alignment in the organ or in the voice box,although the tabs may be separated ,into groups, one for each of themanuals involved.

Combination selector mechanism Y Referring to Figures .4 and 8, inbrackets 23 and 24, I journal a plurality of rods 25, 25a, etc.,

for rotation. The number of these rods may be widely varied, and therewill be a rod for each preset stop combination desired. The rodspreferably extend continuously across all stop-switch and stop-tabcombinations in the organ, although it is within the scope of myinvention, if desired, to provide separate groups of rods for the stoptab groups of the several manuals. The advantage of providing a singlegroup of actuator rods 25, 25a, etc. common to all of the stop tabs isthat this enables me to set up concurrent combinations of voices for theswell, great and pedal manuals whenever desired, while, as respects anyrod, a combination may still be set up pertaining only to a particularmanual.

Above and transverse the groups of rods 25, 25a, I provide an actuatorbar 25 for each stop tab. This bar is shown mounted at its left-hand end(in Figure 4) by a resilient metal strap 2l to a support 2S extendingacross between the brackets 23 and 24. At its right-hand end, the bar isconnected by means of a forked member 29 to the upwardly extending armI3 on the stop tab. This completes the support of the bar 26; and itwill Vbe evident that if the bar be moved in the direction of its lengtheither to the left or right in the figure, it will serve to move thestop tab I0 to its upper orv lower position as the case may be, andconsequently to actuate the stop switch I'I. 'Ihe several actuator rodsserve to move the actuator bars selectively as will presently bedescribed, and hence to elect the movement of the several stop tabs toon and off position in accordance with prearranged patterns.

In connection with each of the actuator bars 2e I provide a series ofmeans 3U, Sila, etc. capable of being engaged by the rods 25, 25a, etc.These elements, as most clearly shown in Figures 9, 10 and 11, eachcomprise a body 3f! and depending, spaced legs 3l and 32 adapted to lieon either side of a bar 25. The bodies such as 3E] are perforated; andare mounted upon the transverse actuator bars such as 26 frictionally,so that while the bodies 3B, 38a, etc. may be moved rotatively withrespect to the bars, a greater force is required to accomplish this thanto move the bars longitudinally for the actuation of the stop tabs I0. Asuitable mode of mounting the elements 36 is illustrated in Figure 6,where a bolt 33 is shown passing through the bar 26 and the body 30,with the interposition of a washer oi frictional material 34therebetween. A compression spring 35 is engaged between a nut 36 on theend of the bolt 33 and the body St, the body having a centraldepression, as shown, serving to center both the spring and thefrictional washer.

The bar 26 for each of the stop tabs I0 will carry as'many of the bodies3o, 39a, etc. as there are rods 25, 25a, etc., by means of which theparticular stop tab is to be actuated. I may pro- Vvide each of thetransverse actuator bars 26 for each of the stop tabs with one of thebodies for each of the longitudinal actuator rods. In usual practicehowever, I assign certain rods 25 to certain keyboards or combinationsof keyboards, employing bodies 3U, 36a, etc. only on those actuator bars26 connected to stop tabs of said certain keyboards or combinationsthereof, and only in those locations on those bars 26 where they mayengage the assigned rods 25. In Figures 1 andv 4 of this application, Ihave illustrated a system in which there are 10 of the rods 25, 25a andin which each of the transverse actuator bars 26 carries 10 of thebodies 30, 30a, etc.

The number of rods and bodies to be actuated thereby may, however, bevaried in accordance with the individual requirements oi any instrument.In order to save space, I have shown a1- ternate ones of the bodies 30,30a, etc. mounted on opposite sides of the actuator bars 26.

I'he rods 25, 25a, etc., throughout their operative length, areflattened as indicated in the several iigures. The distance between thespaced depending legs 3|, 32 of the bodies 30, 30a, etc., may byslightly greater than the longer transverse dimension of the flattenedrods; and the diierence between the longer and shorter transversedimensions of the actuator rods is such that when any rod is turned withits greater cross-sectional dimension vertical, as in Figure 9, and isin inoperative position, the actuator bar bearing the bodies may bemoved in either direction to actuate its stop tab without interferencefrom the rods.

When such a rod is turned so as to have its greater cross-sectionaldimension horizontal, as in Figure 10, it is in actuating position, andmay actuate the transverse bar 26 through the corresponding body 30depending upon the position of that body. If the body at any time ispositioned as indicated in Figure 9, a rotation of the rod 25 willproduce no eiect upon it since the rod will not contact either of thelegs 3|, 32. However, if the position of the body 30 at the time the rod25 is rotated is such that the rod contacts the leg 3|, then the bar 26Will be moved to the left. Contrarivvise, if the leg 32 is so positionedas to be contacted by the rod when it is turned from the solid line tothe dotted line position, the bar 26 will be moved to the right. Therelationship of the body 30 to the rod 25 will depend not alone upon therotative position of the body 3U on the bar 26 but on the longitudinalposition of the bar 26, i. e. on whether or not the particular stop towhich the bar 26 is connected (as hereinabove described) is in the oilor on position.

If I prefer to rotate the rods 25, 25a, etc. through an angle less than90, I may make the longer transverse dimension of the rods greater thanthe distance between the legs of the bodies 3D, 30a, etc.

This series of relationships provides not only for the eiecting ofpredetermined stop combina- Itions upon the actuation, by turning, ofany of the rods 25, 25a, etc., but also permits the easy and convenientestablishment of a combination with respect to each of the rods. This isillustrated in Figures 9, 10 and 1l. Let it be supposed that it isdesired to establish a combination with respect to the rod 25. If thatrod be now turned, as in Figure 10, to a position in which its longercross sectional dimension is horizontal and is caused to remain in thatposition, depression of the stop tab ||l by the i'lnger as shown willresult in a movement of the transverse bar 26 to the right. 'Ihis inturn will tilt the body 30 to the position shown in Figure 10. Thisestablishes the particular stop as one to be turned on as part of thecombination when the rod 25 is turned to actuating position. However,when the rod 25 is turned to non-actuating position the stop tab |0 maybe lifted by the iinger, thus moving the transverse bar 26 to the leftas shown in Figure 11, without changing the position of the body 30 onthe bar.

Similarly, in setting up a combination, if when the rod 25 is placed inactuating position as in Figure 10 and a stop tab is in the down or on",

6 position when the voice represented by that tab is not desired in thecombination, it is only necessary to lift the tab by the finger toremove it from the combination by positioning the body as shown inFigure 9.

In other words, in setting up a combination it is only necessary to turna particular rod to the actuatingposition, and then establish thecombination by turning on or depressing those stop tabs which aredesired as part of the combination, and turning oi or raising those stoptabs which are not desired as part of the combination. When the rodthereafter is turned to non-actuating position, the stop tabs may befreely manipulated by the fingers in any Way desired during the courseof the playing of a musical composition. But if at any time thereafterthe same rod is again turned to actuating position the presetcombination will be established, i. e. those stops preselected aspart'of the combination will be turned on if off, or Will remain on ifalready in that position, while those stops not preset as part of thecombination will be turned o if they happen to be on, or will remain offif in that condition at the time of the actuation of the rod.

It will be understood that in the use of the device, after the variouscombinations have been preselected as described, all rods are turned tothe non-actuating position, leaving all stop tabs free for manipulationby the ngers. In effecting a preset combination, the appropriate rod ofthe group 25, 25-a, etc. is momentarily turned to actuating position andthen is returned to nonactuating position. The preselected combinationwill be established by this momentary action, but the several voices canimmediately be changed.

Selective and driving mechanism ,for the actuator rods For rocking theactuator rods into and out of actuating position, I provide a mechanismwhich will now be described. On a partition or bracket 3`| (see Figure3) in the voice box, I mount an electric motor 38 having a gear box 39with a shaft 40 extending through the partition. One of the face plates4| of a friction clutch is mounted upon this shaft. The other plate ordisc 42 of this clutch is pressed toward the rst by a spring 43 engagingagainst an abutment 44 on the end of a stud mounted to the iirst plate.The purpose of the friction clutch is to permit the operating mechanismto be stopped accurately in its rotative movement, irrespective of anytendency of the motor and associated elements to over-run.

As most clearly shown in Figures 2 and 8, the disc 42 is connected by acurved link 45 to a platform element 46 pivoted as at 41 to a suitablesupport. The link is pivoted to the disc 42 in an on? center position.Rotation of the disc 42 will thus result in raising and lowering theplatform 46, the highest position of the platform being that shown insolid lines in both gures.

The several actuating rods 25, 25a are provided at one end with crankarms 48, 48a etc., and from the ends of these arms I loosely suspend (asmost clearly shown in Figure 5) bar-like elements 49, 49a etc. made ofmagnetic material. Coil springs 5|) engage between the ends of theseelements and brackets on the base of the voice box as shown at 5| inFigure 2, and serve to keep the elements 49, 49a, etc. in generalvertical alignment. At

the lower ends of the elements 49, 49a, etc. I pro- Tvide: hook-shapedconfigurations 52 adapted to be engaged by a turnedaover outer .edge oftheplatform 46 if the elements are drawn toward the platform. Normallythe springs B keep the ele, ments .491, 48a, etc. 'suiciently outwardlybeyond the edge of the platform to avoid such engagement. The elementsthemselves may be drawn toward the platform. into position forengagement, individually, by electromagnets 53,. 53a, etc. It will benoted fromA the arrangement of parts most .clearly illustrated in Figure8 that if anelement de be drawn toward the platform by its electromagnet53 into a position of platform engagement, a lowering of the platformwill result' in a rotation of the actuating rod 25 through the crank arm43, the element 49 acting as a link.. Tofreturnthe rods to non-operativepositionV after they have been so actuated, I preferably provide aresilient return means stronger than 'the spring 5d, as well as asuitable stop means. The elements 69, 45a, etc. may be Drovidedv withangles 54 to engage the platform to assist-in the return of theactuating rods by overcoming the initial friction between the rods 25,25a, etc., and the bodies 3S, 35a, etc, In Figure 8, an arm 55 has .beenshown fastened to the opposite end of the actuating rod 25a. The outerend of this. arm is connected by a spring 56. to a post 5l on the endsupport 23, and a stop 58 is provided for the arm 55 to x the 11011-operative position of the rod.

ln the` circuit of each of the electromagnets 53, 53a, etc., I providean ndividualpush button 59, 59u, etc., a source of power 6G andthewinding 6I of arelay switch for energizing the Ymotor 38. Depression ofany selected one of the series of push buttons 59, 59a, etc. will thusenergize an appropriate oneof the electromagnets 53, 53a, etc., and therelay switch. The relay switch has an armature'EZ and opposed contacts53 and 64, these elements being connected into the power circuit 65 ofthe motor 38. This power circuit also includesA upper and lower limitswitches 66 and 6l associated with the driven disc 42. The lastmentioned switches are normally biased to closed posi-tion, butareadapted to be opened by an abutment on the disc 42 or on the link 45.

If now the push button 59 is depressed, the magnet 53 will be energized,drawing .the element 49 into platformrengaging position. At the sametime the armature 52 of the relay switch will be drawn into contact withthe contact element 64, energizing the motor 38 through the lower limitswitch 6l. The motor will begin to operate, and

'the platform E will be driven downwardly,` pullling upon the elementdi) and rotating the acvmethod of preselecting a stop combination, whichhas been explained above, will thus be carried on by lthe operator whilehe holds depressed a push button appropriate to the particular actuatingrod with respect to which the combinationv is being preset, thusmaintaining the actuating rod in actuating position.

Upon release of the button the armature 62 of the relay switch will riseinto contact with the contact element 63, thus rra-energizing themopending upon the extent of the surface lea; 'independent adjustmentsof the several cams on tor :38 through the upper limit Switch $6.. The

operation of. the. motor. will continueA until the abutment aforesaidopens the limit switch 66 at the completion of a fullV cycle, whereuponthe motor will again be de-energized with the platform 46 in,A itsVupperposition and the actuator rod returnedjto'inoperative position. Itwill be evident thatthe depression and release of any one of the buttons59, 59a, ctc. will thus result in the rotation of an appropriate one ofthe actuator rods to actuating position, and its return to non-operatingposition. In order to prevent premature rise of the armature 62,v if thepush button switch is released immediately, I may provide the relayswitch with a time relay device such as a closed ring of coppersurrounding its magnetic core.

I preferto employ a reversible motor 38 so con-.- neeted intoitspowercircuit that during the first half cycle of revolution of the disc42 the motor will drive it in one direction, while during the secondVhalf cycle or return of the disc to starting position it will be drivenin the opposite direction. This enables me to provide a stop means 69(Figure 2) on the disc 42 and coacting abutments I0 and 7lA on thesupporting partition 3l. |lhis is a safety factor, fixing the Vfull andhalf cycle positions of thedisc 42 and hence the upper and lowerpositions of the platform 46, insuring that the elements 49 and 49a maybe accurately brought into engaging relationship with the platform inits upper position, and providing against over-rotation of the actuatorrods.

At l2,` l2aetc. in Figure 8 have indicated a series of push buttons orother switches in parallelisrn respectively with the push buttons 58,59a, etc. It is frequently desired by the operator Vof the instrumentthatV the preset stop combinations be effectable from differentpositions on the organA console. The use of parallel push buttons orother switches thus enables me to provide duplicate sets for eachmanual, or a series of foot actuated switches adjacent the pedal manual,if .this be desired.

Register crescendo mechanism As apart of the general assembly describedherein, and as part of the mechanism of the voice box, I provide adevice whereby, upon the operation ofv asingle control element in onedirection, a preselectedv series or all of the available voices of theorgan may be brought into effect, either` successively, orsimultaneously. To accomplish this, I journal in the voice box a shaft'i3 shown in Figure 4, and extending generally parallel to the upperfront board of the organ and beneath all or a selected number; of thestop tab mechanisms. Upon this shaft I mount a series of cams 14, onefor each of the stop switches to be actuated, each such cam coactingwith a finger l5 on the actuating lever i9 of its particular stopswitch. The cams may be shaped as shown in Figure? with an actuatingsurface 'ida extending over a substantial arc. Each cam may be providedwith a setscrew 'i6 by means of which its rotative position on the shaft'i3 can be adjusted. It will be understood that as the shaft is causedto rotate, any particular cam 'it will actuate its appropriate stopswitch at a certain angular position of the shaft, depending upon theadjustment of the cam, and will maintain the switch closed duringfurther rotation of the shaft, de-

the shaft any number of stop switches in the .9 group in the voice boxmay be caused to be actuated in any desired sequence or simultaneously.The shaft 13 may be rotated in any was desired. One way is to provide itwith a pinion 1l, meshing with a rack 18, which in turn is connected toany suitable actuator in the control of the operator, such as a footpedal mounted in the lower front board of the organ. Since the cams onshaft 13 act directly on the stop switches Il, their action isindependent of the other operating mechanisms heretofore described, sothat my register crescendo mechanism does not affect the raised orlowered condition of any of the stop tabs, or any voice combinationpreselected through the operation of the combination stop devices.

Special 'voice selectors Normally there are certain voices and/orcouplers in an organ which bear a special relationship to therequirements of musical compositions. For example, the performer, evenwhen employing a preset stop combination, may feel the need of adding toit or subtracting from it one of these special voices or couplers andwithout changing the preset combination as a whole or altering itsreproducability. My mechanism as herein described makes provision forthis need by arranging special actuators for such voices or couplers,which will be effective (in a single manipulation) in opening the switchfor such a voice or coupler if closed, or in closing it if open. I havedevised actuating means for this purpose which accomplishes the desiredeffect without interfering with the mechanisms thus far described, orwith the preset or hand-set stop combinations in eiect at the time ofthe actuation.

In Figure 4 I have shown an angular arm 19 attached to the rearwardlyextending arm I4 of the stop tab mechanism. 'Ihe angular arm has a pairof opposed angularly related cam surfaces 89 and 8l coming together in apoint on its lower edge. Below the arm I have shown a nger 82,resiliently maintained in a centralized vertical position. If thisfinger be driven upwardly it will contact either the cam surface 89 orthe cam surface 8| of the angular arm 19, depending upon the initialposition of the stop tab I9, and, riding down the contacted cam surfaceit will engage a shoulder at the end thereof, moving the arm '19, andhence the stop tab and its associated parts either in one direction orthe other. Thus if the finger 82 be actuated as described, it will raisethe stop tab l if lowered and will lower it if raised.

Referring to Figure 12, it will be seen that the finger 82 is mounted onan axial pivot on the end of a lever 83. The lever is itself pivoted at84 on a bracket 85. The finger 82 is resiliently centered by means of aspring 86 on the lever 83 which engages the lower end of the finger. Thenger extends upwardly through a slot in a bracket element 8'! on thevoice box, which is also provided with a depending stop member 88 forthe lever.

Beyond the pivot 84' the lever is provided with an angular arm 89,connected by flexible cable or bowden transmission element' 90 to a bellcrank 9|. For the selection or elimination of special voices orcouplers, a foot actuator is usually desired. I have shown such a footactuator in Figure 12, comprising a body 92 mounted on the lower frontboard 93 of the organ and perforated to receive a sliding rod element 94having a foot button 95. The bell crank 9| is pivoted as at 96 to abracket 91 on the lower front board 0f the organ; and the inner end ofthe plunger 94 is provided with adjustable means 98 bearing against anarm of the bell crank 9|. A spring 99 may be provided engaging betweenthe bell crank and a bracket |00 on the lower front board of the organto release the transmission 99 after the pressure of the foot is removedand to return the foot button to its outward position.

It will be understood that a mechanism such as has just been describedmay be provided for any one or more stops in the instrument, or even forall of them, although this is not ordinarily desired.

Modifications may be made in my invention without departing from thespirit of it. Having thus described my invention in an exemplaryembodiment, what I claim as new and desire to secure by Letters Patentis:

1. In a combination stop mechanism a stop tab movable to on and offpositions, a stop switch, a connection between said stop tab and saidswitch, a bar mounted for longitudinal movement and having connectionwith said stop tab, a rod mounted for rotative movement transverse saidbar, said rod having unequal transverse dimensions, and a member mountedon said bar and having spaced legs one lying on each side of the rod,said last mentioned member being positionable on said bar so as to beactuatable by said rod.

2. The structure claimed in claim 1 wherein said last-mentioned memberis pivoted to said bar and wherein mechanical resistance means areprovided between said member and said bar, said resistance meansoffering greater resistance to relative movement between said member andsaid bar than the normal resistance of said stop tab to movement inactuating said switch, whereby said member is positionable upon said barby manual movement of said stop tab.

3. In a combination stop mechanism a series of stop tabs mounted formovement to on and off position, a stop switch for each such tab, aconnection between each tab and its switch whereby the switches areactuated by movements of the tabs, a bar for each tab mounted forlongitudinal movement and having connection with the stop tab to move itfrom one position to another, a series of rods common to the severalstop tabs and extending transversely of said bars, said rods mounted forrotative movement, and having unequal transverse dimensions, and aseries of members pivotally mounted on each bar through mechanicalresistance means, said members having legs lying on either side o f therespective rods, said members being positionable upon said bars bymanual movement of the respective stop tabs when said rods are rotatedto positions in which their longer transverse dimension extends in adirection transverse said legs, the shorter transverse dimensionof saidrods being such as to permit movement of said bars in either directionfor the actuation of their respective stop tabs, and the relationship ofparts being such that rotative movement of said rods to a position inwhich their longer transverse dimension is transverse the legs of saidmembers, will produce movement of said bars in either directiondepending upon the instant positions of said bars and the positions ofsaid members thereon.

4. In a combination stop mechanism a series of stop tabs mounted formovement to on and oir positions, a stop switch for each such tab, aconnection between each tab and its switch whereby the switches areactuated by movements of the tabs, a bar for each tab mounted forlongiandrei '11 tudinafl movement vand 'havin-g connection with the stoptab to move it from one position to another, a seriesof rods common tothe several stop tabs and extending transversely of -said bars, saidrods mounted for rotative movement, and having uneoual transversedimensions, and a series of memberspivotall-y mounted on each barthrough mechanical resistance means, lsaid members having legs lying oneither side of the respective rods, said members being positionable uponlsaid bars 'by manual movement of the respective stop` tabs'when saidrods are rotated to positions in which their longer transverse dimensionextends in a direction Atransverse said legs, the "shorter transversedimension of said rods being such as vto permit movement -of said 'barsin either direction for the actuation of their respective stop tabs, andthe relationship of parts being such that rotative movement of said rodsVto a position in which their longer transverse dimension is transversethe legs ofsaid members, will producemovement of said bars in eitherdirection depending upon the instant positions' of vsaid bars and thepositions of vsa-'idl membersv thereon, vand means for rotating saidrods selectively from inoperative tov-operative lposition, together withmeans-for returning said rods to inoperative position.

5. -The vstructure lclaimed vin claim 4 in which lthe means forrotatingfsa'id rods selectively from inoperative tooperative'positionscomprise crank arms on` the ends of the rods,depending link elements on the ends-ef the crank arms, a pivotedplatform common to all such link -members and interengageable therewith,resilient means for holding said link Vmembers 'in positions ofnonengagement with lsaid platform, vand magnetic means for bringing saidlink members selectively into engagement with said platform.

6. The structure claimed in claim 4 in which the means for rotating saidrodslselectively from inoperative to operative positions comprise crankarms on the ends of the rods, depending link .elements on theends ofthecrank arms, a pivoted platform common to all'such link members andinterengageable therewith, resilient means for holding said link membersin positions of non- .engagement with Vsaid platform, and magnetic meansfor bringing Vsaid link members selectively into engagement with saidplatform, and means for moving said' platform comprising a motor, .acrank, and. alinkage connection between said .crank and said platform,andv cyclical control mechanism for Vsaidmotor for causing it to movesaid platform in one direction and return said platform to startingposition.

7. The structure claimed in claim 4 in which the means for rotating saidrods selectively from inoperative to operative positions comprise crankarms on the ends of the rods, .depending link elements on the ends ofthe crank arms, a pivoted platform common to all such .link members andinterengageable therewith, resilient means for holding said linkmembersin positions of .nonengagement with Asaid platform, and magnetic meansfor bringing vsaid link members selectively into engagement with saidplatform, .and means for moving said platform comprising a motor, acrank, and a linkage connection between said crank and said platform,and cyclical control umechanism for said motor for causing it to movesaidA platform in one. direction and return said platform to startingposition, an operating circuit for said motor and an inter-connectionbetween said operating circuit, said magnetic means i2 and selectiveswitch devices individually connected to the separate magnetic `mea-nswhereby operation of said motor can be caused to rotate Y any one ofsaid rods selectively.

8. The structure'elaimed in claim '7 including a friction clutch havingan .element driven 'by said motor, said crank being connected 'to saidelement, wherein said operating circuit causes operation of said vmotorfor a half cycle in onedirecticn and furthe remaining half cycle in theopposite direction, and including stop means located on said frictionclutch element and arranged V4to coact with `an -abutmentprovided on v'asupprt to determine the upper and lower positions of vsaid platform.

9. The structure claimed in claim '7 including a friction clutch havingan element driven by said motor, said crank being connected tor saidelement, wherein said operating circuit causes operation of said motorfor a half cycle in one dlrection and for the remaining half cycle `inthe opposite direction, and including stop means located on saidfriction clutch element and arranged to coact with an abutmentlprovidedA `on a support to determine the upper and lower positions ofsaid platform, and wherein lsaid control circuit includes opposed'limit-switches and a relay for completing forward and' reverse connections to'said motor respectively through said limit switches, wherein said limitswitches are respectively actuated by van abutment means in 'connectionAwith said friction clutch member, and Wherein said circuits Aconnectingsaid electromagnetic means 'are connected incommon to said relay switch.

10. The structure claimed in claim 7 including a friction clutch hav-ingan element driven by said motor, said crank being connected to saidelement, `wherein said operating circuit causes i operation of saidmotor for a half cycle in one direction and for the remaining half cyclein the opposite direction, and including stop means located on saidfriction clutch element and arranged to coactA with an abutment providedon a support to determine the upper and lower positions of saidplatform,and wherein said conrol circuit includes opposed limit `switches and arelay for completing forward and reverse connections to `said motorrespectively through said limit switches, wherein said limit switchesare respectively actuated by an abutment means in connection with saidfriction clutch member, and wherein said circuits connectingsaidelectromagnetic means are connected in common 'to said relay switch, andwherein -said relay switch includes time delay mechanism.

l1. The structure claimed in claim '7 including a friction clutch havingan element driven by said motor, said crank being connected to saidelement, wherein said operating circuit causes operation of said motorfor a half cycle in one direction and for the remaining half cycle inthe opposite direction, and including stop `means located on saidfriction clutch element and `ar ranged to coact with an abutmentprovided on a support to determine the upper and lower positions of saidplatform, and wherein said control circuit includes opposed limitswitches and a relay for completing forward' and reverse connecticns tosaid motor respectively through said `limit switches, wherein said limitswitches "are respectively actuated by an abutment means in connectionwith said friction clutch member, and wherein said circuits connectingsaid electromjgnetC .means .are connected in common to said cludes timedelay mechanism, and wherein selectively operable switches in additionto the first mentioned switches are connected respectively in paralleltherewith so that the stop selector mechanism can be operated from aplurality of positions.

12. The structure claimed in claim 11 wherein the connection between thestop tabs and their respective switches is a loose connection permittingoperation of the switches with the stop tabs in the off position, andincluding a shaft common to a plurality of said switches mounted forrotation in proximity thereto, said shaft being provided with adjustablecams for operating said switches, and including a foot pedal connectedwith said shaft to rotate it whereby to actuate a varying number of saidswitches in accordance with the angular amount of such rotation.

13. The structure claimed in claim 11 wherein the connection between thestop tabs and their respective switches is a loose connection permittingoperation of the switches with the stop tabs in the off position, andincluding a shaft common to a plurality of said switches mounted forrotation in proximity thereto, said shaft being provided with adjustablecams for operating said switches, and including a foot pedal connectedwith said shaft to rotate it whereby to actuate a varying number of saidswitches in accordance with the angular amount of such rotation, certainof said stop tabs at least having doublefaced cam elements in connectiontherewith, actuators for said cam elements serving upon actuation in onedirection to move said stop tabs from either position to the other, andconnections between said actuator elements and foot actuated operatingelements.

14. In a musical instrument of the type wherein the timbre of the tonesproduced is selected by v means of electric circuits, the combination ofa plurality of electric switches respectively connected in saidcircuits, stop tabs manually movable between a timbre-selecting positionand a timbre-rejecting position with respect to said switches, cammounting strips located behind said tabs and respectively movablelongitudinally thereby, a rotatable cam bar mounted adjacently andperpendicularly to said strips, cam members each comprising a baseportion rotatably engaging one of said strips through mechanicalresistance means and two leg portions straddling said cam bar, means forrotating said bar about its longitudinal axis from a substantiallyparallel position with respect to said legs to a substantiallyperpendicular position with respect to said legs, each said cam, for agiven position of its respective strip and tab, having a iirst position,wherein neither of its legs is engageable by said cam bar upon rotationthereof and a second position wherein one of said legs is engageable bysaid bar upon rotation thereof to force said strip to shift said tab toits other position, said positions of said cam being changeable by themanual movement of a respective tab while said bar is in saidperpendicular position with respect to said legs.

15. Mechanism comprising parallelly arranged elongated memberslongitudinally movable between two extreme positions, a rotatable barmounted adjacent to and transverse said members, cams each comprising abase portion rotatably engaging one of said elongated Lmembers throughmechanical resistance means and two leg portions straddling said bar,said bar being of round-edged substantially rectangular cross-sectionwhere straddled by said legs, means for rotating said bar about itslongitudinal axis between a position wherein the long axis of saidrectangular section is substantially parallel to said legs and aposition wherein said axis is substantially perpendicular to said legs,each said cam for a given position of its respective elongated memberhaving one position wherein neither of its legs is engageable by saidbar upon rotation thereof and another position wherein one of said legsis engageable by said bar upon rotation thereof to force said elongatedmember to shift from one of said two positions to the other, theposition of a cam with respect to its elongated member being changeableby forcing said elongated member from one of said two positions to theother while the rectangular section of the bar straddled thereby is insaid perpendicular position with respect to said legs.

16. Mechanism as claimed in claim 14 including manually movableactuating means in connection with said elongated members and movablethereby during the movement of said elongated member from one of saidtwo positions to the other.

17. Mechanism as claimed in claim 15, including resilient means inconnection with said actuating means operative to assist in saidmovements as said elongated members approach either of said twopositions.

18. In a combination stop mechanism, a series of stop tabs mounted formovement to on and off positions, a stop switch for each tab, and aconnection between each tab and its switch whereby the switches areactuated by movements of the tabs, the connections between the stop tabsand their respective switches being a loose connection permittingoperation of the switches with the stop tabs in the oif position, ashaft common to a plurality of said switches mounted for rotation inproximity thereto, said shaft bearing cams for operating said switches,and a foot pedal connected with said shaft to rotate it whereby toactuate a varying number of said switches in accordance with the angularamount of such rotation.

19. In a combination stop mechanism, a series of stop tabs mounted formovement to on and off positions, a stop switch for each such tab, aconnection between each tab and its switch whereby the switches areactuated by movements of the tabs, a bar for each tab mounted forlongitudinal movement and having a connection with the stop tab to moveit from one position to another, a series of rods common to the severalstop tabs and extending transversely of said bars, said rods mounted forrotative movement and having unequal transverse dimension, and a seriesof members pivotally mounted on each bar through mechanical resistancemeans, said members having legs lying on either side of respective rods,said members being positionable upon said bars for manual movement ofthe respective stop tabs so as to be actuable by said rod upon rotationthereof.

20. The structure claimed in claim 19 wherein the connection between thestop tabs and their respective switches is a loose connection permittingoperation of the switches, with the stop tabs in the off position, andincluding a shaft common to a plurality of said switches mounted forrotation in proximity thereto, said shaft being pro- 1.5 16 vided withadjustable cams for operating `said saidactuator elements and footactuated operat- .switches., and. .including Va foot pedal .connected.ing elements providedtherefor.

with said shafty to rotate it whereby to actuate RAYMOND P. MORE., 'aAvvarying number of .sadrswitches in accordance withv the angular amountof such rotation, .5 REFERENCES CITED '21 The Structure m 31mm 19 mWhlch Cer The following references are of record in the tain of 4saidstop tabs at least have doub1efaced fue of this patent:

cam elements in connection therewith, actuators y forsad cam elementsserving upon actuation in UNITED STATES PATENTS one direction to movesaid stop tabs from either io Number vName Date position to the other,and connections between 1,747,733 Patterson Feb..18, 1930

